RF-MEMS Switch and Phase Shifter Optimized for W-Band

This paper presents the optimization of the low-complexity RF-MEMS technology for W-Band, the fabricated switches and phase shifters. All devices are fabricated on a thinned silicon substrate using only one metallization. The basic W-Band switch used for the phase shifter is presented in detail showing a very wide band RF-behaviour with an almost constant insertion loss of about -0.3 dB from 50 - 100 GHz. The 3-bit phase shifter itself with the design frequency of 76.5 GHz is realized using one loaded-line and two switched-line phase shifter elements. The mean insertion loss of the whole phase shifter is -5.3 dB and the phase deviation was calculated to be 13.4deg. Furthermore an extension to a 4-bit phase shifter by the use of a dual-state microstrip line phase shifter element is given. In addition, a short switching-time of the switches of only 15 mus was measured.